Probabilistic human health risk assessment of trace elements exposure in crayfish

In this study, we collected 385 crayfish samples from five provinces (Hubei, Hunan, Anhui, Sichuan, and Jiangsu) of the Yangtze River Basin in China during July 2021, explored trace element enrichment and spatial distribution, and used a Bayesian approach to assess the health risks of trace elements during crayfish consumption. Due to the limited sample size, variability in exposure time, and lack of dietary information, the results of risk assessment were generally highly uncertain. The results showed that the distribution and elemental composition of crayfish differed significantly by province, and the concentrations of essential elements (Cr and Ni) were generally higher than those of nonessential and toxic elements (V, As, Cd, Hg, and Pb). In risk assessment, the posterior cumulative probability lines of the target hazard quotient (THQ) and hazard index (HI) showed acceptable non-carcinogenic risk levels. Furthermore, the posterior curves of incremental lifetime cancer risk (ILCR) values for Cr and Ni reached the medium risk threshold of 1 x 10-5 corresponding to a cumulative probability of 60 %, indicating an unacceptable medium carcinogenic risk level for nearly 40 % of people. The Bayesian approach provided a better understanding of the risk levels to which percentages of the population were exposed.